//     Zepto.js
//     (c) 2010-2014 Thomas Fuchs
//     Zepto.js may be freely distributed under the MIT license.

;(function($){
var touch = {},
touchTimeout, tapTimeout, swipeTimeout, longTapTimeout,
longTapDelay = 750,
gesture

function swipeDirection(x1, x2, y1, y2) {
return Math.abs(x1 - x2) >=
  Math.abs(y1 - y2) ? (x1 - x2 > 0 ? 'Left' : 'Right') : (y1 - y2 > 0 ? 'Up' : 'Down')
}

function longTap() {
longTapTimeout = null
if (touch.last && touch.el) {
  touch.el.trigger('longTap')
  touch = {}
}
}

function cancelLongTap() {
if (longTapTimeout) clearTimeout(longTapTimeout)
longTapTimeout = null
}

function cancelAll() {
if (touchTimeout) clearTimeout(touchTimeout)
if (tapTimeout) clearTimeout(tapTimeout)
if (swipeTimeout) clearTimeout(swipeTimeout)
if (longTapTimeout) clearTimeout(longTapTimeout)
touchTimeout = tapTimeout = swipeTimeout = longTapTimeout = null
touch = {}
}

function isPrimaryTouch(event){
return (event.pointerType == 'touch' ||
  event.pointerType == event.MSPOINTER_TYPE_TOUCH)
  && event.isPrimary
}

function isPointerEventType(e, type){
return (e.type == 'pointer'+type ||
  e.type.toLowerCase() == 'mspointer'+type)
}

$(document).ready(function(){
var now, delta, deltaX = 0, deltaY = 0, firstTouch, _isPointerType

if ('MSGesture' in window) {
  gesture = new MSGesture()
  gesture.target = document.body
}

$(document)
  .bind('MSGestureEnd', function(e){
	var swipeDirectionFromVelocity =
	  e.velocityX > 1 ? 'Right' : e.velocityX < -1 ? 'Left' : e.velocityY > 1 ? 'Down' : e.velocityY < -1 ? 'Up' : null;
	  if (swipeDirectionFromVelocity && touch.el) {
	  touch.el.trigger('swipe')
	  touch.el.trigger('swipe'+ swipeDirectionFromVelocity)
	}
  })
  .on('touchstart MSPointerDown pointerdown', function(e){
	if((_isPointerType = isPointerEventType(e, 'down')) &&
	  !isPrimaryTouch(e)) return
	firstTouch = _isPointerType ? e : e.touches[0]
	if (e.touches && e.touches.length === 1 && touch.x2) {
	  // Clear out touch movement data if we have it sticking around
	  // This can occur if touchcancel doesn't fire due to preventDefault, etc.
	  touch.x2 = undefined
	  touch.y2 = undefined
	}
	now = Date.now()
	delta = now - (touch.last || now)
	touch.el = $('tagName' in firstTouch.target ?
	  firstTouch.target : firstTouch.target.parentNode)
	touchTimeout && clearTimeout(touchTimeout)
	touch.x1 = firstTouch.pageX
	touch.y1 = firstTouch.pageY
	if (delta > 0 && delta <= 250) touch.isDoubleTap = true
	touch.last = now
	longTapTimeout = setTimeout(longTap, longTapDelay)
	// adds the current touch contact for IE gesture recognition
	if (gesture && _isPointerType) gesture.addPointer(e.pointerId);
  })
  .on('touchmove MSPointerMove pointermove', function(e){
	if((_isPointerType = isPointerEventType(e, 'move')) &&
	  !isPrimaryTouch(e)) return
	firstTouch = _isPointerType ? e : e.touches[0]
	cancelLongTap()
	touch.x2 = firstTouch.pageX
	touch.y2 = firstTouch.pageY

	deltaX += Math.abs(touch.x1 - touch.x2)
	deltaY += Math.abs(touch.y1 - touch.y2)
  })
  .on('touchend MSPointerUp pointerup', function(e){
	if((_isPointerType = isPointerEventType(e, 'up')) &&
	  !isPrimaryTouch(e)) return
	cancelLongTap()

	// swipe
	if ((touch.x2 && Math.abs(touch.x1 - touch.x2) > 30) ||
		(touch.y2 && Math.abs(touch.y1 - touch.y2) > 30))

	  swipeTimeout = setTimeout(function() {
		if(touch.el){
		  touch.el.trigger('swipe')
		  touch.el.trigger('swipe' + (swipeDirection(touch.x1, touch.x2, touch.y1, touch.y2)))
		  touch = {}
		}                
	  }, 0)

	// normal tap
	else if ('last' in touch)
	  // don't fire tap when delta position changed by more than 30 pixels,
	  // for instance when moving to a point and back to origin
	  if (deltaX < 30 && deltaY < 30) {
		// delay by one tick so we can cancel the 'tap' event if 'scroll' fires
		// ('tap' fires before 'scroll')
		tapTimeout = setTimeout(function() {

		  // trigger universal 'tap' with the option to cancelTouch()
		  // (cancelTouch cancels processing of single vs double taps for faster 'tap' response)
		  var event = $.Event('tap')
		  event.cancelTouch = cancelAll
		  if(touch.el){
		  touch.el.trigger(event)
		  }
		  // trigger double tap immediately
		  if (touch.isDoubleTap) {
			if (touch.el) touch.el.trigger('doubleTap')
			touch = {}
		  }

		  // trigger single tap after 250ms of inactivity
		  else {
			touchTimeout = setTimeout(function(){
			  touchTimeout = null
			  if (touch.el) touch.el.trigger('singleTap')
			  touch = {}
			}, 250)
		  }
		}, 0)
	  } else {
		touch = {}
	  }
	  deltaX = deltaY = 0

  })
  // when the browser window loses focus,
  // for example when a modal dialog is shown,
  // cancel all ongoing events
  .on('touchcancel MSPointerCancel pointercancel', cancelAll)

// scrolling the window indicates intention of the user
// to scroll, not tap or swipe, so cancel all ongoing events
$(window).on('scroll', cancelAll)
})

;['swipe', 'swipeLeft', 'swipeRight', 'swipeUp', 'swipeDown',
'doubleTap', 'tap', 'singleTap', 'longTap'].forEach(function(eventName){
$.fn[eventName] = function(callback){ return this.on(eventName, callback) }
})
})(Zepto);
